Thomas w



No. elzso. Patented ont. la, 139:3.4

I T. w. McKENzlE.

TELEscoPlc STRUCTURE.

(Application med Mar. 1, 199s.)

(No Model.)

3@ M E I I im 1 i, v B

l BY l/ ma cams PETERS co, morau'mo.. WASHINGTONv o. c.

THOMAS IV. -MOKENZIE, OF

TELESCOFICv INDIANAPOLIS, INDIANA.

STRUCTURE.,

sPEeIrreAToN farming part of Letters Patent No. 612,630, dated october 1s, '1898.

g Application nei nach 1,1393.'

T0 all whom t 11m/y con/067172,:

Be it known that I, THOMAS W. MCKENZIE, a citizen of the United States, residing at Indianapolis, in the county of Marion and State of Indiana, have'invented certain new and useful Improvements in Telescopic Structures, of which the following is a specification. 1

The object of my, said invention is to provide a convenient and efficient means whereby the two membersof a telescopic structure may be eonvenientljflt and efficiently locked in relation toeaeh other at any point desired.l

This invention is applicable to many uses 5 but I have designedfit especially for the seatposts and steering-heads of bicycles, although I expect to use the same for any purpose to Which it may be applicable.

Said invention will be first fully described, and the novel features thereof then pointed out in the claims.

The accompanying drawings illustrate that form of a telescopic structure composed of two cylindrical tubes, one slidably mounted in the other, said structure being provided With or embodying my present invention.

In said drawings, Figure l is a side elevation of the adjacent portions of two such telescopic tubes provided With attaching or locking means embodying my said invention 5 Fig. 2, alongitudinal vertical section through the outer tube, showing the inner tube in ele'- vation Fig. 3, a transverse sectional viewon the dotted line 3 3, showing the device in its locked position; Fig. 4, a similar View on the dotted line 4t 4, showing the device in its unlocked position; Fig. 5, an elevation or plan when the parts are in the position shown in Figli 5 Fig. G,a similar view when the parts are in the position shown in Fig. 3; Fig. 7, an elevation or plan of an alternative construction in which the dog or pawl is positioned longitudinally, instead of transversely or circumferentially, of the tubes; Fig. 8, a view on the dotted line 8 S in Fig. 7, and Fig. 9 a perspective View of the head end of theouter tube When .constructed as shown in Figs. 7 and 8.

In said drawings the portions marked A represent the-outer member of the telescopic structure; B, the inner member; C, a dog or pawl pivoted in the outer member and adapted Serial No. 672,156. (No model.)

to engage with the inner member, and D a ring surrounding the end of the outer member.

The members A and B are adapted to move longitudinally in relation to'each other, the member B being of appropriate size to iit within the member A. They are prevented from rotary movement in ,relation to each other by means of a spline s in one `which enters a groove in the other. The outer member A has an enlarged orthiclrened `head a, within which a suitable recess or recesses are formed to receive the dogs or pawls C. I prefer to have two of these recesses and two dogs arranged diametrically opposite to each other, as shown in the drawings, although but one may be used Where desired, and of course a greater number may be employed up to the limit of available space therefor.`

The member B has a number of `engaging points, as perforations l), in its surface arranged at such distances apart as may be desired to accommodate the various adjustments suitable to the purposefor which the structure is tobe used. When the device is be Aemployed in bicycles, these ,perforations may be approximately one-half inch apart, as usually adjustments of a half inch or thereabout are suflicient for this purpose. As Will be observed by an inspection of the draW- ings, the recesses in the enlarged head a of the outer member terminate at one end in a corresponding perforation.

` The. dogs C operatesubstautially in the manner of levers, the central portions of the. recesses in the head portions a of the outer members being raised, as shown in Figs. 3 and 4, andserving as fulcrums, upon which the under sides of said dogs reist at a middle point. At one end each of said dogs has a point c, which is adapted to pass through the perforation at the ends of corresponding re-` cesses in the head a of the outer member and into engagement with one of the perforations or engaging points of the inner member. When the dogs are in this position, the members A and B are locked in relation to each other, and any relative ,longitudinal move ment is prevented. Said dogs have raised or wedge-shaped ends at the outsides thereof by which their positions are shifted, as will now be explained.

The ring D surrounds thehead end a of i IOO the outer member and has slots cut through` its central portion or such recesses cut therein as to form interior cam-surfaces, which enable said ring to operate iirst upon one end and then upon the other of the dogs C, rocking said dogs over their central fulcrum or.I

pivot-points and throwing them into or out" of engagement, as will be readily understood upon an inspection of the drawings, espe-if cially Figs. 3 and 4, which show the two po sitions. Extending out from the head a' through a suitable slot in the ring D is a studn a, which serves to limit the movement ofi said ring D. It is also desirableto provide`l` means whereby said ring D may be locked at the end of its movement. A simple and effective; meansis ,to provide a thumbfnfut di to be carriedrbyrthe stud av (whichfis screw-,` threaded for the purpose) and to form asmallff boss d, which will sink into enlarged ends of@ the slot in the ring D. Thus, as will Abef; readilyseemby unscrewing the thumb-nut*-` cl until'the boss is withdrawn `from theen larged end of the slot the ring vwillbeiireeito move; but'after it vhas `been adjusted said;y ring can be securely locked in place byLturn-:f ing down said thumb-nut, forcing its'iboss cli .intothey enlarged end ofthe slot. f

'Having thus fully described my said inven-r p tion,what I claim as new, and desire to secure*l by .Lette1's;Patent, is- 5' `Il. In a telescopic structure,'the combination of the inner member provided with a :se-f 4ries of engaging points arranged at suitableli` distances apart longitudinally thereof, theg outer member provided with recesses .fori pawls or dogs, saidpawls or dogs mounted inf said recesses and adapted to engage with said engaging points, and a `surrounding ringl adapted to be moved circumferentially of said.' structure and provided with cam-surfacesfor operating said dogs, whereby said members? may be shifted longitudinally 'relatively'tof each other'and locked at any predetermined adjusted position. y

2. The combination, in a telescopic :struc-.f ture, of the inner memberB having perfora-i tions or'lnotches lathe outermemberhavingy an enlarged head with recesses therein,vthe= -inner wall thereof being raisedcentrallyto form a pivot or fulcrum, dogs or pawls mount-i4 ed in said recesses and operating over said@ `pivot or fulcrum and provided with endsl adapted toengage with suitable engaging points in the inner member, and a surrounding ring extending over said dogs or pawls and having recesses formed in its interior side, the formation of the adjacent portions of said dogs .or pawls and said ring being such that a-camrrelation exists between the two, whereby said dog or pawl may be operated vby the rotation of said ring, substantially as set forth.

3. The combination, in a telescopic structure, of the inner and the outer telescopic members, dogs or pawls carried by one telescopicmemberand adapted to engage with the other, and a ring surrounding and adapted to operate said pawls, said several parts being constructed, arranged and operating substan- `tiallyas set forth, whereby said inner'and :outer :telescopic members may be adjusted longitudinally in lrelation .E to4 eachl other, and .locked at anypredetermined.longitudinallyadj usted position.

fl. The combination, in a telescopicstructure, ofthe inner and outer telescopicl members adapted to be adjusted longitudinally of f each other, 'dogs or, pawls mounted in the head on1 the: outer member and adapted to engage with? the inner member, a lring surrounding andadapted to operateithesame, and a lock- 1ing-device ywherebyfsaid ring may'be locked toeither positiomwhereby said-inner and :outer telescopic members maybe adjusted longitudinally in relation toiA each other, and vlocked at any predetermined Vlongitudinallyadjusted position, substantially as set forth.

l 5. The combination, in a-telescopic struc- :ture, of an inner telescoping member, an outer telescoping member, a dog or pawl, mounted in one telescoping member and adapted to engage with the other telescoping member, and a surrounding ring movable circumferentially yandfa'dapted to operate said 'dog or pawlwherev'by said' inner and outeri telescoping members H maybe adjusted longitudinally in relation to -each other, andlocked at any predetermined yadjusted position.

In witness whereof 'I have hereunto set my hand and seal, at Indianapolis, Indiana, this 26th day of February, A. D. 18%.

"THOMAS W.'MCKENZIE. [L s] Witnesses:

CHESTER BRADFORD, J AMES A. WALSH.

IOO 

